Mulch Many gardeners leave their gardens alone for a few days and when they come back it’s full of weeds and they become discouraged. Mulch will help prevent weeds from taking over your garden. This means you can spend more time enjoying your garden and less time pulling up unwanted plants. The best time to mulch is after the soil has warmed up and you are ready to start planting. In Zone 4 Canada, this is usually the 2nd week of June if the weather has been warm and sunny. Use black plastic or landscape fabric to help speed up warming if it has been a cool, cloudy spring. Different mulches have different properties but most of them do the same basic jobs. They all: keep the soil cool during the day and warm at night, reduce the amount of water evaporation from 10 to 50%, keep weeds from germinating between the wanted plants, (some) improve the texture and fertility of the soil, and keep the rain from eroding or crusting the soil. If you have clay soil then good mulching will definitely help your garden. Mulch also helps to keep you and your plants cleaner. Bark
They are slow to rot and very attractive when used in the gardens, around shrubs and trees or in container gardens. If you surround the base of trees and shrubs with bark mulch it’s easier to mow if you raise the blade of the lawn mower high enough to pass right over it while cutting the grass. Bark will trap moisture in the soil below and prevent weeds from sprouting by cutting off the light that reaches the soil. It enables air to circulate around the roots of the plants and stops the soil from compacting. Black Plastic You can reduce the use a layer of thin, black plastic to stop weeds germinating in your garden. Buy a big enough piece to cover the entire area you want to plant and leave a little extra around the edges.
It will help raise the soil’s temperature by 6°F (14°C) in the spring. You can leave it on your garden as mulch and nothing will grow through it or under it because neither sunlight nor air will get to the soil. Rainwater may pool on it, which you may want to drain off once in a while. If you save it and water your plants with it later it will do them a world of good. Push the plastic down into shallow trenches pushed in soil along the side of each row and the water will run to a spot where you can collect it. Heat-loving plants like tomatoes and watermelons will benefit from a layer of black plastic laid on the ground around their roots. Don’t use it over clay soil because it blocks air circulation and will cause the ground to compact. Cardboard You can use cardboard in your garden as mulch or to create walkways where you don’t want anything to grow. Carefully cut open cardboard boxes and cut them to the width you want. Place them on the soil where you want to mulch. Overlay the edges so weeds can’t sprout up in between. Hold the cardboard down with a second layer of mulch like hay or bark. It will slowly get soggy and rot so don’t use it were you know the ground will stay wet. If you have a problem with earwigs in your garden this is not the best solution for your garden. Carpet Some kinds of carpet are made for use outdoors but you can use some kinds of indoor carpet for one or two seasons. Don’t use canvas or rubber-backed carpet because they rot quickly and make a mess. Use dark colours if you want to help to warm the soil. Lay the carpet down where you want to mulch and overlap where 2 pieces join. Use chalk to mark out your rows and holes for your seedlings if your want to cover a larger area with carpet. Ask an adult’s help to cut the carpet with heavy scissors or a craft knife. In the fall, after you have harvested the garden, rinse off the carpet and allow it to dry completely before storing it in the garage or shed for the winter. Grass Clippings Grass clippings make great mulch and they are available almost every week right after the lawn gets mowed! Because you will get grass seeds in your garden you may need to weed a little more often. If you can get grass that doesn’t have any seed heads on it you might avoid that particular problem. If your lawn was recently fertilized wait until it the first mowing after a good rainfall or watering before you use the clippings on the garden or you could burn the plants roots. Always spread out the clippings evenly and not more than 1" deep (2.5 cm) or it will suffocate your plants trying to grow through it. If it’s too thick it will also start to rot and turn into a smelly, slimy mess. Hay Hay can contain weed seeds but if you always keep mulch on your garden the weeds won’t get a chance to sprout. Hay rots slowly and will improve the condition of your soil. There are lots of air pockets in hay that worms love. You can entice them into your garden and they will fertilize the soil for you. Hay is an especially good conditioner for clay soil. Use a flake of hay, a strip at least 1" thick (2.5 cm) and place them side-by-side. If you plan to use hay with newspaper add just enough of it hold the newspaper down. Straw Straw has the same properties as hay put it has fewer weeds and less nutrients. It may contain a few seeds but the benefits outweigh the drawbacks. Straw holds moisture well and adds nutrients to the soil as it slowly decomposes. Landscape Fabric Landscape fabric comes in many sizes and lengths. It’s inexpensive, lightweight, water and air permeable. It will block most seeds from reaching the soil, which is what will prevent most seeds from germinating. Don’t put your fabric down until after the soil has had a chance to dry out and you have tilled it well. The black colour will help warm up the soil but some weeds may start to sprout under it. Once the soil is warm enough to plant you can use chalk to mark out your rows and holes for your seedlings. You can use scissors to cut holes in the fabric and put in your seedlings. Add a layer of mulch if you want to hold in the moisture and keep unwanted plants from germinating under the fabric. Newspaper Newspapers can be effective at reducing weeds and holding in moisture. Don’t do this on a windy day or the whole neighbourhood will be reading your news! You will have to place at least 12 pages over each area and overlap the edges. Cover them with hay, straw, grass clippings or sawdust to hold them down.
If your garden has earwigs you may want to choose different mulch because these pests love to read the ‘sports section’ while they chew on your plants. Pine Needles Pine needles will add more acidity to the soil so be careful where you use it because most plants don’t like very acidic soil. Blueberries love pine needle mulch so save it for them. Spread a thick layer of needles around the base of your bushes and keep it out of the rest of the garden. Super Smother Mulch If you’re willing to wait a year or two before planting you can simply mulch weeds away. Even the toughest weeds will eventually succumb to Super Smother Mulch Pull up by the roots or cut down all the existing weeds in your garden area and water it well. For small, annual weeds lie on about 12 sheets of newspaper and weigh it down with hay, straw or any other heavy mulch. For tough perennials, you may need to pile the newspapers several inches thick or use cardboard making sure to overlap the edges. Cover the whole area with bark, wood chips, shredded leaves or other attractive organic mulch. Leave the Smother Mulch in place for an entire season then remove it or till it into the soil if it is mostly decomposed. If the weed roots aren’t dead you can leave the Smother Mulch on for a second season. You can plant large crops like pumpkins, winter squash or tomatoes in holes cut through the mulch. Make sure you pull out any weed shoots that poke through. Wood Chips Wood chips are usually a little larger than bark chips. They will prevent evaporation and hold down weed seedlings. They make nice soil cover for container gardens and around trees and shrubs inside a retaining border.
Do not run over them with a lawnmower. They can damage the blades and spit out sharp slivers. If you want to use them in your yard around trees, put a border between the grass and the chips to stop your mower from running over them. You can even add a little purchased bark to give rough chips a more polished finish. Weeds Finally, there’s a good use for weeds, believe it or not! You can use weeds uprooted from the garden as mulch as long as they are laid on top of either newspaper, cardboard, black plastic or landscape fabric. If you put them right on top of tilled soil some of them may try to re-root themselves. If the seeds are ripe, they could also shake loose and take root. Without the blocking layer of mulch underneath you could end up pulling more weeds than you started with. Compost the weeds if they are particularly hardy. Once they rot they make excellent soil conditioner. |
